Porous Nanofiber Membrane: Rational Platform for Highly Sensitive Thermochromic Sensor

Abstract

Thermochromic sensors provide an intuitive and real‐time solution for monitoring the local temperature with naked eyes. Conventional thermochromic sensors often utilize either solution‐type or dense film‐type platforms, which are suboptimal morphologies for exposing a large number of dye molecules to the surface, leading to low sensitivity and sluggish responding speeds. Herein, this article introduces rational synthetic routes to fabricate highly sensitive nanofiber (NF) sensor membranes loaded with thermochromic dyes (C3H6N6·CH2O)x‐loaded nanofibers (NFs) sensor membranes by alignment‐controllable electrospinning techniques (x–y perpendicular and rotary). The NF‐based porous sensor membranes exhibit two‐ to fivefold improved thermochromic sensitivity (ΔRGB) compared to those of dense film‐type sensors at 31.6–42.7 °C. This is attributed to the uniform distribution of dyes throughout the porous NF structure (≈95.7%), which exhibits excellent light transmittance that is 10–30‐fold higher than that of film‐type sensors. Based on the available shape‐conforming synthetic strategies, this article further demonstrates wearable thermochromic sensors in the forms of mask‐, patch‐, and bracelet‐type devices, which can accurately monitor body temperature in real time.

Achieving broad availability of SARS-CoV-2 detections via smartphone-based analysis

“…Smartphone-based tests can convert signals into precise digital data that may show more sensitive and accurate readings than visual observations; smartphones can also control the progress of detections through a well-designed program; at the same time, due to smartphones are widely used, so it doesn't take much of a burden [ [44] , [45] , [46] , [47] , [48] , [49] ]. Some smartphone-based tests have already shown great promise for the accurate and sensitive detections of various analytes [ [50] , [51] , [52] , [53] ]. Until now, a few smartphone-based detections have been investigated for nucleic acid analysis.…”

Conformational Flexibility-Controlled Piezochromic Behavior of Organic Fluorophores

“…Organic luminescent materials with stimuli-responsive behaviors have attracted worldwide attention owing to their practical applications in biomedical, , optoelectronic, sensor, , and anticounterfeiting fields. , Mechanical forces, especially hydrostatic pressure, as types of readily available and common external stimuli, can significantly manipulate the conformations and molecular packing of organic luminescent materials in aggregated states, thus adjusting their emission colors and intensity. − For example, the fluorescent colors of 3-bis­(4-(3,6-di- tert -butyl-9 H -carbazol-9-yl)­phenyl)­fumaronitrile switch between green and orange upon 0.5 MPa external pressure due to the slipping-angle change of π-stacking . The fluorescence emission of 9,10-bis­(( E )-2-(pyrid-2-yl)­vinyl)­anthracene red-shifts and quenches upon pressurization because of the enhanced π–π stacking .…”

“…Organic luminescent materials with stimuli-responsive behaviors have attracted worldwide attention owing to their practical applications in biomedical, 1,2 optoelectronic, 3 sensor, 4,5 and anticounterfeiting fields. 6,7 Mechanical forces, especially hydrostatic pressure, as types of readily available and common external stimuli, can significantly manipulate the conformations and molecular packing of organic luminescent materials in aggregated states, thus adjusting their emission colors and intensity.…”

Triphenylamine, Carbazole or Tetraphenylethylene-Functionalized Benzothiadiazole Derivatives: Aggregation-Induced Emission (AIE), Solvatochromic and Different Mechanoresponsive Fluorescence Characteristics

“…Fluorescence emissions can also be modulated by external stimuli. The type of stimulation can be divided into photochromic, electrochromic, thermochromic, mechanochromic, and so on [ 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 ]. The emission properties of mechanochromic fluorescence materials can be controlled by physical channels, such as anisotropic grinding, shearing, or rubbing [ 36 , 37 , 38 , 39 , 40 ].…”